Quote Originally Posted by phibermon View Post
Next year I was outside and I noticed frogs hopping in from under the gate to get to the pond - a path that was previously completely blocked off by the topography of the garden - did they breadcrumb to the general vicinity and then left-right until they found a gap? did those frogs just happen to come from that direction and get lucky?
As far as frogs go. They have extremely powerful smelling capability. In fact it is so powerful that they can detect increased moisture in the air. So when wind blows over your pond the air is moisturized and then carried away. Frogs can then follow this trail of moisturized air back to your pond. And they can do this from a range of even up to 10 km or 6 miles.
And frogs are not the only animals capable of this. My mom was born in a village which was founded about 300 years ago when during the drought season pigs (which also have very acute smell) wandered over 15 km (roughly 10 miles) to a fresh water spring which was the only natural spring that season that hasn't dried. In fact from the time of when this spring was discovered for the first tim and till today nobody has ever seen it dry up yet.

Any way if you look at all the different way animals use for path-finding. Well let us just say that in your lifetime you probably won't be able to write algorithms that mimic most of them.
Here are just some of the most amazing ways animals use for orientation and path-finding:
1. Birds are known for being able to detect earth magnetic field and thus location of earths magnetic poles. This allows them to navigate great distances without much problems. But scientists are warning us that with all the electromagnetic interference we are causing we might be eventually causing them havoc in their navigation. And birds are not the only animals that have this ability. Many others have but are not so dependent on it like the birds are.
2. Bees remember the path they took from their hive to the flower by simply remembering how long they flew in straight lien and when they turned and into which way. They also have a clever way of communicating this information to other bees through so called "bee dance".
3. Ants always leave chemical trail behind them so they can always return back to the nest. Even ore by manipulating the chemical they use on this trail they are leaving specific message of what kind od destination does this path leaves to (food, danger, etc).

Sorry for going a bit off-topic but for me this is interesting stuff especially when I see computers trying to mimic/simulate it.